health: update comments.

Test: pass
Bug: 63702641
Change-Id: Iedf1bfe37a356e5801a09e313ac186fdc73668ca
diff --git a/health/2.0/libhealthhalutils/Android.bp b/health/2.0/libhealthhalutils/Android.bp
index 1bd934b..5686520 100644
--- a/health/2.0/libhealthhalutils/Android.bp
+++ b/health/2.0/libhealthhalutils/Android.bp
@@ -14,6 +14,8 @@
  * limitations under the License.
  */
 
+// Convenience library for (hwbinder) clients to choose the correct health
+// service instance.
 cc_library_static {
     name: "libhealthhalutils",
     srcs: ["HealthHalUtils.cpp"],
diff --git a/health/2.0/libstoragehealthdefault/Android.bp b/health/2.0/libstoragehealthdefault/Android.bp
index 986e1ef..cef04fe 100644
--- a/health/2.0/libstoragehealthdefault/Android.bp
+++ b/health/2.0/libstoragehealthdefault/Android.bp
@@ -1,5 +1,22 @@
-// Copyright 2018 The Android Open Source Project
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 
+// Default implementation for (passthrough) clients that statically links to
+// android.hardware.health@2.0-impl but do no query for storage related
+// information.
 cc_library_static {
     srcs: ["StorageHealthDefault.cpp"],
     name: "libhealthstoragedefault",